<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
</html>
<script>
    var max=prompt('','');
    for(var i=0;i<9;++i){
        var tmp=prompt('','');
        if(tmp>max){
            max=tmp;
        }
    }
    alert(max);
</script>